Questions from Database Systems


Q: The DBMS does not guarantee that the semantic meaning of the transaction

The DBMS does not guarantee that the semantic meaning of the transaction truly represents the real-world event. What are the possible consequences of that limitation? Give an example.

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Q: List and discuss the five transaction properties.

List and discuss the five transaction properties.

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Q: What does serializability of transactions mean?

What does serializability of transactions mean?

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Q: What is a transaction log, and what is its function?

What is a transaction log, and what is its function?

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Q: What is a scheduler, what does it do, and why

What is a scheduler, what does it do, and why is its activity important to concurrency control?

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Q: What is a lock, and how, in general, does

What is a lock, and how, in general, does it work?

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Q: What are the different levels of lock granuality?

What are the different levels of lock granuality?

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Q: What is SQL performance tuning?

What is SQL performance tuning?

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Q: What is the difference between a rule-based optimizer and a

What is the difference between a rule-based optimizer and a cost-based optimizer?

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Q: Using the query results in Problem 35 as your basis, write

Using the query results in Problem 35 as your basis, write a query to generate the total number of invoices, the invoice total for all of the invoices, the smallest of the customer purchase amounts, t...

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